Effects of Chronic Ozone Exposure on the Growth of Trifolium subterraneum and Trifolium repens

1981 ◽  
Vol 8 (5) ◽  
pp. 405 ◽  
Author(s):  
DC Horsman ◽  
AO Nicholls ◽  
DM Calder
Keyword(s):  
Trifolium Subterraneum ◽  
Dry Weight ◽  
Plant Part ◽  
Ozone Exposure ◽  
Rapid Decline ◽  
Relative Growth ◽  
Area 6 ◽  
Leaf Necrosis ◽  
Net Assimilation ◽  
Total Dry Weight

Plants of Trifolium subterraneum and T. repens were exposed to 9 parts per hundred million ozone for 4 h per day, 5 days per week for 5 weeks. Leaf necrosis was apparent after the first week of exposure and this was followed by the death of some leaves and stems. At the end of the exposure, significant reductions were found in total dry weight (30-40%), plant part dry weight and leaf area (ͭ6 30%). Ozone caused a rapid decline in relative growth rate which was related to a reduction in net assimilation rate.

Growth Responses of Dactylis glomerata, Lolium perenne and Phalaris aquatica to Chronic Ozone Exposure

1980 ◽  
Vol 7 (5) ◽  
pp. 511 ◽  
Author(s):  
DC Horsman ◽  
AO Nicholls ◽  
DM Calder
Keyword(s):  
Leaf Area ◽  
Dactylis Glomerata ◽  
Dry Weight ◽  
Ozone Exposure ◽  
Growth Responses ◽  
Relative Growth ◽  
Leaf Chlorosis ◽  
The Difference ◽  
Net Assimilation ◽  
Total Dry Weight

D. glomerata, L. perenne and P. aquatica were exposed to 9 parts per hundred million ozone for 4 h per day on 5 days per week for 5 weeks. The grasses responded similarly and significant changes in growth were generally observed only at the end of the exposure. The changes in growth were accompanied by slight leaf chlorosis. Total dry weight and yield (above-ground dry weight) were significantly reduced (14-21%) by the treatment. Root growth was impaired the most, followed by stem and then leaves. Specific leaf area was generally lower in ozone-treated plants but the difference was not significant. Effects on relative growth rate were mainly due to the decrease in net assimilation rate, leaf area ratio remaining relatively unchanged.

Distribution of zinc and copper in seedlings of subterranean clover (Trifolium subterraneum L.) in solution culture

1956 ◽  
Vol 7 (6) ◽  
pp. 495 ◽  
Author(s):  
DS Riceman ◽  
GB Jones
Keyword(s):  
Dry Matter ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Dry Weight ◽  
Solution Culture ◽  
Rapid Decline ◽  
Trifoliate Leaf ◽  
Plant Parts ◽  
Total Dry Weight ◽  
Substantial Change

Changes in the distribution of zinc, copper, and dry matter in seedlings of Trifolium subterraneum L. var. Bacchus Marsh grown in solution cultures which were supplied with copper but not with zinc have been traced during the first 40 days after germination. Increase in total dry weight was accompanied by a rapid decline in the concentration of zinc in the plant parts examined. Symptoms of zinc deficiency were recognizable in the third trifoliate leaf by the time the leaflets opened, 33 days after germination. At that time the concentration of zinc in leaf plus petiole had fallen to 14 p.p.m. in the dry matter. There was a continual net loss of zinc from the cotyledons. A marked increase in the amount of copper present in roots, and in leaf plus petiole, occurred soon after the addition of copper to the cultures 20 days after germination, but no substantial change was observed in the amount of copper present in the cotyledons or in the hypocotyl plus growing point. These latter tissues had previously lost small amounts of copper.

scholarly journals The effect of high iron doses (Fe2+) on the growth of broccoli plants (Brassica oleracea var. Italica)

2014 ◽  
Vol 32 (1) ◽  
pp. 22-28 ◽  
Author(s):  
Jaime E. Peña-Olmos ◽  
Fánor Casierra Posada ◽  
Misael A. Olmos-Cubides
Keyword(s):  
Growth Rate ◽  
Brassica Oleracea ◽  
Dry Weight ◽  
Dry Mass ◽  
Iron Sulfate ◽  
Relative Growth ◽  
Excess Iron ◽  
Absolute Growth ◽  
Net Assimilation ◽  
Total Dry Weight

Tests were carried out under greenhouse conditions in Tunja (Colombia) in order to evaluate the effect of Fe2+ toxicity on the growth of broccoli plants. 'Legacy' hybrid Brassica oleracea var. Italica plantlets were grown in glass containers with a nutritive solution. Iron sulfate was added to the substrate in order to produce excess iron at concentrations of 100 and 200 mg L-1; a control without iron sulfate applications was used. The following evaluations were made: leaf area, total dry weight of the plants, distribution of dry mass (DM) in the different organs, absolute growth rate, relative growth rate, net assimilation rate and the root:shoot ratio. The total DM decreased drastically in the plants subjected to excess Fe2+, the growth indices progressively decreased with increases in the Fe2+ concentrations in the substrate and the distribution of DM in the organs varied as a function of the needs of the plants, with 15.85 and 11.10% less DM in the roots of the plants subjected to Fe2+ than in the control plants, at 100 and 250 mg L-1, respectively.

Effects of Temperature and CO2Concentration on the Growth of Cotton (Gossypium hirsutum), Spurred Anoda (Anoda cristata), and Velvetleaf (Abutilon theophrasti)

Weed Science ◽  
1988 ◽  
Vol 36 (6) ◽  
pp. 751-757 ◽  
Author(s):  
David T. Patterson ◽  
Maxine T. Highsmith ◽  
Elizabeth P. Flint
Keyword(s):  
Dry Matter ◽  
Dry Weight ◽  
Net Assimilation Rate ◽  
Assimilation Rate ◽  
Short Term ◽  
Leaf Weight ◽  
Matter Production ◽  
Total Plant ◽  
Net Assimilation ◽  
Total Dry Weight

Cotton, spurred anoda, and velvetleaf were grown in controlled-environment chambers at day/night temperatures of 32/23 or 26/17 C and CO2concentrations of 350 or 700 ppm. After 5 weeks, CO2enrichment to 700 ppm increased dry matter accumulation by 38, 26, and 29% in cotton, spurred anoda, and velvetleaf, respectively, at 26/17 C and by 61, 41, and 29% at 32/23 C. Increases in leaf weight accounted for over 80% of the increase in total plant weight in cotton and spurred anoda in both temperature regimes. Leaf area was not increased by CO2enrichment. The observed increases in dry matter production with CO2enrichment were caused by increased net assimilation rate. In a second experiment, plants were grown at 350 ppm CO2and 29/23 C day/night for 17 days before exposure to 700 ppm CO2at 26/17 C for 1 week. Short-term exposure to high CO2significantly increased net assimilation rate, dry matter production, total dry weight, leaf dry weight, and specific leaf weight in comparison with plants maintained at 350 ppm CO2at 26/17 C. Increases in leaf weight in response to short-term CO2enrichment accounted for 100, 87, and 68% of the observed increase in total plant dry weight of cotton, spurred anoda, and velvetleaf, respectively. Comparisons among the species showed that CO2enrichment decreased the weed/crop ratio for total dry weight, possibly indicating a potential competitive advantage for cotton under elevated CO2, even at suboptimum temperatures.

scholarly journals Influence of Soil Amendment on the Relative Growth Rate and Net Assimilation Rate of Phaseolus vulgaris and Vigna aconitifolia

2020 ◽  
pp. 1-13
Author(s):  
E. A. Effa ◽  
A. A. J. Mofunanya ◽  
B. A. Ngele
Keyword(s):  
Growth Rate ◽  
Phaseolus Vulgaris ◽  
Relative Growth Rate ◽  
Soil Amendment ◽  
Dry Weight ◽  
Organic Manure ◽  
Assimilation Rate ◽  
Vigna Aconitifolia ◽  
Relative Growth ◽  
Net Assimilation

Background: Soil pH is one of the most important factors that contribute to crop growth and productivity. The present research was designed to assess the influence of soil amendment using organic manure and agricultural lime on the relative growth rate (RGR) and net assimilation rate (NAR) of Phaseolus vulgaris and Vigna aconitifolia grown on soils from different locations. Methodology: The three locations were: Akamkpa, Calabar Municipality and Odukpani. The pH for the three soil locations were 4.0, 7.0 and 9.0, respectively. The treatments were; control (0 g), OM1 (100 g organic manure), OM2 (200 g organic manure), AL1 (100 g agricultural lime), AL2 (200 g agricultural lime), OM1 + AL1 (50 g organic manure + 50 g agricultural lime) and OM2 +AL2 (100 g organic manure and 100 g agricultural lime). Results: Results obtained on the RGR of the leaf dry weight of P. vulgaris treated with OM2 was the highest (0.50 g/wk) followed by OM1 (0.41 g/wk). OM1 + AL1 had the highest RGR of the stem dry weight of P. vulgaris grown on soil from Calabar Municipality. In the RGR of the root dry weight, OM2 had the highest mean value in both plants grown on Akamkpa soil. Results obtained at 4 weeks after planting (WAP) revealed that there was significant (P<0.05) increase in NAR of plants grown on soil from Akamkpa. The highest NAR was obtained for V. aconitifolia treated with OM2 (0.0447 g/wk) followed by OM2 + AL2 (0.0057 g/wk) for both V. aconitifolia and P. vulgaris. P. vulgaris grown on Akamkpa and Odukpani soils treated with AL2 (0.0032 g/wk), OM1 + AL1 (0.0041 g/wk) and OM2+ AL2 (0.0062 g/wk) had the highest NAR at 8 WAP. Conclusion: The RGR and NAR of the two bean varieties were improved following treatments with organic manure and agricultural lime.

A study of growth in swards of timothy and meadow fescue. I. Uninterrupted growth

1958 ◽  
Vol 51 (3) ◽  
pp. 347-352 ◽  
Author(s):  
R. H. M. Langer
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Leaf Size ◽  
Dry Weight ◽  
Meadow Fescue ◽  
Area Index ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Number Of Leaves ◽  
Total Dry Weight

1. Swards of S. 48 timothy and S. 215 meadow fescue growing alone or together were sampled at intervals of 3 weeks throughout the season. The number and weight of leaves, stems and ears were determined, and leaf area was estimated.2. Despite high rainfall, the total number of tillers in both species declined from the beginning of the experiment until early July, but increased again from then onwards until the original complement had been approximately restored. The number of leaves failed to show a corresponding increase in the autumn because each tiller carried fewer leaves than earlier in the year.3. In the spring total dry weight increased more rapidly in meadow fescue than in timothy which in turn out-yielded meadow fescue later in the season. Both species attained their greatest dry weight soon after ear emergence, a period which was marked by considerable crop growth and relative growth rates.4. Leaf area index reached a maximum before total dry weight had increased to its highest level, but then declined in both species. Meadow fescue differed from timothy by producing a second crop of foliage after the summer with a leaf area index of about 7. This second rise appeared to be due mainly to increased leaf size in contrast to timothy whose leaves became progressively smaller towards the end of the season.5. The differences in growth between the species discussed with reference to their dates of ear emergence which in this experiment differed by about 6 weeks.

Phenyl indole-3-thiolobutyrate increases growth of transplanted 1-0 red oak

1988 ◽  
Vol 18 (1) ◽  
pp. 131-134
Author(s):  
Daniel K. Struve ◽  
W. Timothy Rhodus
Keyword(s):  
Leaf Area ◽  
Butyric Acid ◽  
Dry Weight ◽  
Area Ratio ◽  
Leaf Area Ratio ◽  
Red Oak ◽  
Relative Growth ◽  
Auxin Treatment ◽  
Net Assimilation

The basal 1 cm of taproot of dormant bareroot 1-0 red oak (Quercusrubra L.) seedlings were given a 3-s dip in 20, 40, or 80 mM concentrations of indole-3-butyric acid (IBA), phenyl indole-3-thiolobutyrate (P-ITB), or equal parts IBA and P-ITB at 20 or 40 mM concentrations. Sixty control seedlings were dipped in 95% ethanol, while 30 seedlings were used for each auxin treatment. Seedlings were potted on May 12, 1986, and grown outdoors. At the end of the 104-day study period, all concentrations of IBA and P-ITB significantly increased number of roots regenerated (from 5.3 with 20 mM IBA to 11.9 for 80 mM IBA) compared with control seedlings. However, P-ITB-treated seedlings produced significantly more leaves (20–24) and leaf area (320–472 cm2), and up to 10 g more dry weight than IBA and non-auxin-treated seedlings. P-ITB treated seedlings had higher relative growth and net assimilation rates and lower leaf area ratio than IBA-treated or control seedlings. Seedlings treated with 20 mM of equal parts IBA and P-ITB were similar to P-ITB-treated seedlings while seedlings treated with the 40 mM IBA and P-ITB combination were similar to IBA-treated seedlings.

scholarly journals Fitness Cost of Imazamox Resistance in Wild Poinsettia (Euphorbia heterophylla L.)

Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1859
Author(s):  
Saeid Hassanpour-bourkheili ◽  
Mahtab Heravi ◽  
Javid Gherekhloo ◽  
Ricardo Alcántara-de la Cruz ◽  
Rafael De Prado
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Specific Leaf Area ◽  
Dry Weight ◽  
Area Ratio ◽  
Fitness Cost ◽  
Seed Plant ◽  
Growth Indices ◽  
Relative Growth ◽  
Net Assimilation

Wild poinsettia (Euphorbia heterophylla L.) is a difficult-to-control weed in soybean production in Brazil that has developed resistance to herbicides, including acetolactate synthase inhibitors. We investigated the potential fitness cost associated to the Ser-653-Asn mutation that confers imazamox resistance in this weed. Plant height, leaf and stem dry weight, leaf area and seed production per plant as well as the growth indices of specific leaf area, leaf area ratio, relative growth rate and net assimilation in F2 homozygous resistant (R) and susceptible (S) wild poinsettia progenies were pairwise compared. S plants were superior in most of the traits studied. Plant heights for S and R biotypes, recorded at 95 days after planting (DAP), were 137 and 120 cm, respectively. Leaf areas were 742 and 1048 cm2 in the R and S biotypes, respectively. The dry weights of leaves and stems in the S plants were 30 and 35%, respectively, higher than in the R plants. In both biotypes, the leaves had a greater share in dry weight at early development stages, but from 50 DAP, the stem became the main contributor to the dry weight of the shoots. The R biotype produced 110 ± 4 seed plant−1, i.e., 12 ± 3% less seeds per plant than that of the S one (125 ± 7 seed plant−1). The growth indices leaf area ratio and specific leaf area were generally higher in the S biotype or similar between both biotypes; while the relative growth rate and net assimilation rate were punctually superior in the R biotype. These results demonstrate that the Ser-653-Asn mutation imposed a fitness cost in imazamox R wild poinsettia.

Competition, Growth Rate, and CO2Fixation in Triazine-Susceptible and -Resistant Smooth Pigweed (Amaranthus hybridus)

Weed Science ◽  
1983 ◽  
Vol 31 (4) ◽  
pp. 438-444 ◽  
Author(s):  
William H. Ahrens ◽  
E. W. Stoller
Keyword(s):  
Growth Rate ◽  
Dry Weight ◽  
Dry Matter Accumulation ◽  
Lower Growth ◽  
Amaranthus Hybridus ◽  
Relative Growth ◽  
Lower Growth Rate ◽  
Net Assimilation ◽  
Synthetic Capacity ◽  
Smooth Pigweed

Triazine-susceptible (S) and -resistant (R) biotypes of smooth pigweed (Amaranthus hybridusL.) were grown in the field under competitive conditions at varying initial proportions of S and R plants. R plants were less competitive than S plants as measured by accumulation of total above-ground dry weight and seed dry weight. S and R plants were also grown in the field under non-competitive conditions at 100, 40, and 10% light. Growth rate at 10% light did not differ between S and R plants. At the two higher light intensities, dry-matter accumulation 11 weeks after seeding was about 40% less in the R plants. At 100% light, relative growth rate and net assimilation rate were lower in the R plants by about 3.5 and 19%, respectively. The light- and CO2-saturated rates of CO2fixation in intact leaves of glasshouse-grown R plants were 20% less than those in S plants. An apparent 10 and 20% greater number of chlorophyll molecules per photosystem II reaction center in R plants (as compared with S plants) grown in the field at 40 and 100% light, respectively, did not explain differences between the S and R biotypes in photo synthetic capacity. The S and R plants did not differ in specific leaf weight or chlorophyll content on a leaf-area basis. Lower growth rate of R plants may be responsible for inferior competitive ability of R biotypes and could be the result of an impaired photosynthetic capacity.

scholarly journals The effect on the growth of Lemna minor of alternating periods of light and darkness of equal length

1938 ◽  
Vol 125 (838) ◽  
pp. 115-123 ◽  
Keyword(s):  
Growth Rate ◽  
Lemna Minor ◽  
Stomatal Closure ◽  
Continuous Light ◽  
Dry Weight ◽  
Culture Solution ◽  
Single Individual ◽  
Lighting Conditions ◽  
Net Assimilation ◽  
Total Dry Weight

Garner and Allard (1931) showed that plants grown in alternating light and dark periods of equal duration respond differently according to the length of the period. They found that the growth of Cosmos sulphureus, for example, was progressively poorer as the alternating periods decreased from 12 hr. to 1 min., after which it improved rapidly so that at 5 sec. intermittency the plants were of fairly normal appearance, i.e. like those in 12 hr. alternations. No measurements of these effects however were made. Portsmouth (1937) carried out similar experiments with cucumber plants, and has shown that the increase in total dry weight is greatest in continuous light, only slightly less in 12 hr. alternations and considerably less in 1 min. alternations. He suggests that the effects observed were related to carbohydrate deficiency occasioned by a falling net assimilation rate and partial closure of the stomata at 1 min. alternations. Gregory and Pearse (1937) have shown that short alternating light and dark periods are accompanied by a closing of the stomata in Pelargonium , and here again the effect was at a maximum with intermittencies of about 1 min. duration. In view of the above results it was decided to repeat and extend the growth-rate determinations with Lemna minor , which is simple in structure and is eminently suitable for experimental work under laboratory conditions. It had also the advantage, as its stomatal opening does not change, that should results similar to those of Garner and Allard, and Portsmouth, be obtained it would be possible to assess the value of stomatal closure at rapid intermittencies on growth rate. 2. Experimental procedure Two different stocks of Lemna were employed, one, coming originally from the Chelsea Physic Garden, had been used previously in this de-partment, while the other was a fresh stock obtained from Sutton. Each stock was established in the first instance from a single individual. In all cases colonies were grown under 12 hr. alternating light and darkness for 14 days before being placed under the lighting conditions in which their growth rate was to be measured. Apart from the light factor all environmental conditions were the same during the preliminary 14 days as when measurements were being made. The plants were grown in a culture solution made up as follows: CaH 4 (PO 4 ) 2 . H 2 O 0·100 g., KNO 3 0·800 g., MgSO 4 . 7H 2 O 0·25 g., FeCl 3 0·002g., distilled water 1000 ml. In some cases the water used was condensed on glass, in others on copper. The culture solution was changed only when the plants were being measured; it was not aerated but always shaken up with air immediately before being used. The solution was made up in amounts of 2 litres, but as the number of colonies to be supplied varied from time to time the several lots lasted for different periods.

Sign in / Sign up

Export Citation Format

Share Document